[VOL-2235] Mocks and interfaces for rw-core
This update consists of mocks that are used by the rw-core
during unit testing. It also includes interfaces used for unit
tests.
Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/counter.go b/vendor/github.com/prometheus/client_golang/prometheus/counter.go
new file mode 100644
index 0000000..d463e36
--- /dev/null
+++ b/vendor/github.com/prometheus/client_golang/prometheus/counter.go
@@ -0,0 +1,277 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+ "errors"
+ "math"
+ "sync/atomic"
+
+ dto "github.com/prometheus/client_model/go"
+)
+
+// Counter is a Metric that represents a single numerical value that only ever
+// goes up. That implies that it cannot be used to count items whose number can
+// also go down, e.g. the number of currently running goroutines. Those
+// "counters" are represented by Gauges.
+//
+// A Counter is typically used to count requests served, tasks completed, errors
+// occurred, etc.
+//
+// To create Counter instances, use NewCounter.
+type Counter interface {
+ Metric
+ Collector
+
+ // Inc increments the counter by 1. Use Add to increment it by arbitrary
+ // non-negative values.
+ Inc()
+ // Add adds the given value to the counter. It panics if the value is <
+ // 0.
+ Add(float64)
+}
+
+// CounterOpts is an alias for Opts. See there for doc comments.
+type CounterOpts Opts
+
+// NewCounter creates a new Counter based on the provided CounterOpts.
+//
+// The returned implementation tracks the counter value in two separate
+// variables, a float64 and a uint64. The latter is used to track calls of the
+// Inc method and calls of the Add method with a value that can be represented
+// as a uint64. This allows atomic increments of the counter with optimal
+// performance. (It is common to have an Inc call in very hot execution paths.)
+// Both internal tracking values are added up in the Write method. This has to
+// be taken into account when it comes to precision and overflow behavior.
+func NewCounter(opts CounterOpts) Counter {
+ desc := NewDesc(
+ BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+ opts.Help,
+ nil,
+ opts.ConstLabels,
+ )
+ result := &counter{desc: desc, labelPairs: desc.constLabelPairs}
+ result.init(result) // Init self-collection.
+ return result
+}
+
+type counter struct {
+ // valBits contains the bits of the represented float64 value, while
+ // valInt stores values that are exact integers. Both have to go first
+ // in the struct to guarantee alignment for atomic operations.
+ // http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+ valBits uint64
+ valInt uint64
+
+ selfCollector
+ desc *Desc
+
+ labelPairs []*dto.LabelPair
+}
+
+func (c *counter) Desc() *Desc {
+ return c.desc
+}
+
+func (c *counter) Add(v float64) {
+ if v < 0 {
+ panic(errors.New("counter cannot decrease in value"))
+ }
+ ival := uint64(v)
+ if float64(ival) == v {
+ atomic.AddUint64(&c.valInt, ival)
+ return
+ }
+
+ for {
+ oldBits := atomic.LoadUint64(&c.valBits)
+ newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+ if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) {
+ return
+ }
+ }
+}
+
+func (c *counter) Inc() {
+ atomic.AddUint64(&c.valInt, 1)
+}
+
+func (c *counter) Write(out *dto.Metric) error {
+ fval := math.Float64frombits(atomic.LoadUint64(&c.valBits))
+ ival := atomic.LoadUint64(&c.valInt)
+ val := fval + float64(ival)
+
+ return populateMetric(CounterValue, val, c.labelPairs, out)
+}
+
+// CounterVec is a Collector that bundles a set of Counters that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. number of HTTP requests, partitioned by response code and
+// method). Create instances with NewCounterVec.
+type CounterVec struct {
+ *metricVec
+}
+
+// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
+// partitioned by the given label names.
+func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
+ desc := NewDesc(
+ BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+ opts.Help,
+ labelNames,
+ opts.ConstLabels,
+ )
+ return &CounterVec{
+ metricVec: newMetricVec(desc, func(lvs ...string) Metric {
+ if len(lvs) != len(desc.variableLabels) {
+ panic(makeInconsistentCardinalityError(desc.fqName, desc.variableLabels, lvs))
+ }
+ result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
+ result.init(result) // Init self-collection.
+ return result
+ }),
+ }
+}
+
+// GetMetricWithLabelValues returns the Counter for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Counter is created.
+//
+// It is possible to call this method without using the returned Counter to only
+// create the new Counter but leave it at its starting value 0. See also the
+// SummaryVec example.
+//
+// Keeping the Counter for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Counter from the CounterVec. In that case,
+// the Counter will still exist, but it will not be exported anymore, even if a
+// Counter with the same label values is created later.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc (minus any curried labels).
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+ metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
+ if metric != nil {
+ return metric.(Counter), err
+ }
+ return nil, err
+}
+
+// GetMetricWith returns the Counter for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Counter is created. Implications of
+// creating a Counter without using it and keeping the Counter for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc (minus any curried labels).
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+ metric, err := v.metricVec.getMetricWith(labels)
+ if metric != nil {
+ return metric.(Counter), err
+ }
+ return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. Not returning an
+// error allows shortcuts like
+// myVec.WithLabelValues("404", "GET").Add(42)
+func (v *CounterVec) WithLabelValues(lvs ...string) Counter {
+ c, err := v.GetMetricWithLabelValues(lvs...)
+ if err != nil {
+ panic(err)
+ }
+ return c
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. Not returning an error allows shortcuts like
+// myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
+func (v *CounterVec) With(labels Labels) Counter {
+ c, err := v.GetMetricWith(labels)
+ if err != nil {
+ panic(err)
+ }
+ return c
+}
+
+// CurryWith returns a vector curried with the provided labels, i.e. the
+// returned vector has those labels pre-set for all labeled operations performed
+// on it. The cardinality of the curried vector is reduced accordingly. The
+// order of the remaining labels stays the same (just with the curried labels
+// taken out of the sequence – which is relevant for the
+// (GetMetric)WithLabelValues methods). It is possible to curry a curried
+// vector, but only with labels not yet used for currying before.
+//
+// The metrics contained in the CounterVec are shared between the curried and
+// uncurried vectors. They are just accessed differently. Curried and uncurried
+// vectors behave identically in terms of collection. Only one must be
+// registered with a given registry (usually the uncurried version). The Reset
+// method deletes all metrics, even if called on a curried vector.
+func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) {
+ vec, err := v.curryWith(labels)
+ if vec != nil {
+ return &CounterVec{vec}, err
+ }
+ return nil, err
+}
+
+// MustCurryWith works as CurryWith but panics where CurryWith would have
+// returned an error.
+func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec {
+ vec, err := v.CurryWith(labels)
+ if err != nil {
+ panic(err)
+ }
+ return vec
+}
+
+// CounterFunc is a Counter whose value is determined at collect time by calling a
+// provided function.
+//
+// To create CounterFunc instances, use NewCounterFunc.
+type CounterFunc interface {
+ Metric
+ Collector
+}
+
+// NewCounterFunc creates a new CounterFunc based on the provided
+// CounterOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a CounterFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe. The function should also honor
+// the contract for a Counter (values only go up, not down), but compliance will
+// not be checked.
+func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc {
+ return newValueFunc(NewDesc(
+ BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+ opts.Help,
+ nil,
+ opts.ConstLabels,
+ ), CounterValue, function)
+}